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Douglas S. Hall Gregory W. Henry Dietmar Böhme Peter A. Brooks Sandy Chang Ales Dolzan George L. Fortier Robert E. Fried Russell M. Genet Bruce S. Grim James Hannon Darrel B. Hoff Kevin Krisciunas Howard J. Landis Howard P. Louth Larry P. Lovell Paul Nielsen Bobby E. Powell Harry D. Powell Don Pray Thomas R. Renner Charles W. Rogers Stephen Shervais Douglas M. Slauson Samuel Slote Harold J. Stelzer Arthur J. Stokes Jack C. Troeger Louis C. Turner Norman F. Wasson Kenneth W. Zeigler 《Journal of Astrophysics and Astronomy》1991,12(4):281-287
We present photoelectric photometry of λ And never before published, obtained between February 1982 and December 1990 at 29
different observatories. Then we combine it with all other photometry available to us (previously published, contained in
the I.A.U. Commission 27 Archives, and obtained with the Vanderbilt 16-inch automatic telescope but not yet published), to
yield a 14.8-year data base. Analysis reveals a long-term cycle in mean brightness, with a full range of 0m.15 and a period of 11.4 ± 0.4 years. Because most of our new photometry was concentrated in the 1983-84 observing season,
we analyze that one well-defined light curve with a two-spot model. Spot A keeps a 0m.04 amplitude throughout four rotation cycles whereas the amplitude of spot B diminishes from 0m.09 down almost to 0m.03. The spot rotation periods were 55d.9 ± 0d.6 and 520d.8 ± 1d.0, respectively. 相似文献
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Results-based funding (RBF) is a governance concept that is rapidly becoming the mainstream paradigm for international collaborations in the environmental sector. While portrayed as a compromise solution between market-based mechanisms and unconditional donations, the implementation of RBF is revealing new conflicts and contradictions of its own. This paper explores the application of RBF for Reducing Emissions from Deforestation and Forest Degradation (REDD+) by describing the discursive conflicts between recipient (i.e., Brazil) and donor (i.e., Norway and Germany) countries of the Amazon Fund about what constitutes “results” or “performance.” Although all parties agree that the financial transfers to RBF should be based on past emission reductions in relation to a historical baseline, they hold clashing interpretations about temporal (i.e., past or future) and epistemological (i.e., how to measure) aspects of the results these payments are intended for. Firstly, while Brazil emphasizes that it deserves a reward of USD 21 billion for results achieved between 2006 and 2016, donor countries have indicated an interest in paying only for most recent results as a way to incentivize further reductions. Secondly, while all parties believe that Amazon Fund should support policies to reduce deforestation, donor countries have revealed concerns that the performance of the Amazon Fund projects in generating further reductions has not been measured in a rigorous manner. This suggests that donor countries may consider making changes to current RBF mechanisms or getting involved in new forms of finance. 相似文献
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Andreas Muschinski Ror Frehich Mike Jensen Ron Hugo Axel Hoff Frank Eaton Ben Balsley 《Boundary-Layer Meteorology》2001,98(2):219-250
Two state-of-the-art, high-resolution, in situ turbulence measurement systems, which can be deployed at altitudes well above the atmospheric surface layer, are compared: the Tethered Lifting System (TLS) of the Cooperative Institute for Research in Environmental Sciences (CIRES)at the University of Colorado, Boulder, Colorado, and the helicopter-borneturbulence measurement system HELIPOD of the Technical UniversityBraunschweig, Germany, and the University of Hanover, Germany. Whilethe CIRES TLS is a fixed-point platform, HELIPOD is a moving platform.On the basis of data taken with the two systems in separate field campaigns,the system capabilities are quantified and discussed. Criteria for instrumentalrequirements are presented. It is shown that both the CIRES TLS and HELIPODare well suited for measuring fine-scale turbulence that is characterized by very small temperature structure parameters 106 K2 m–2/3 and smaller) and very small energy dissipation rates (10-7 m2 s-3 and smaller). The authors are not aware of any other turbulence measurement systems that have similar capabilities and can be deployed at altitudes of up to several kilometres. The HELIPOD is ideal for high-resolution horizontal measurements while the TLS is ideal for high-resolution vertical measurements using multiple sensors attached to a suspended line. 相似文献
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In a laboratory experiment to simulate mine tailings disposal into a coastal inlet of British Columbia, initial rapid increases in dissolved iron, copper and lead were observed in the first three hours with subsequent slow decreases to background values within one month. Manganese and nickel increased slowly during the experiment while cadmium and zinc did not increase. 相似文献
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Fisher's behaviour with individual vessel quotas—Over-capacity and potential rent: Five case studies
Frank Asche Hkan Eggert Eyjolfur Gudmundsson Ayoe Hoff Sean Pascoe 《Marine Policy》2008,32(6):920-927
Internationally, individual vessel quotas (IVQ) have become an increasingly popular management tool. The main attraction of IVQs is the incentives they create for cost savings, autonomous capacity adjustment and, subsequently, rent generation. In this paper, the extent to which different IVQ systems have facilitated resource rent generation and capacity adjustment in five European countries—Denmark, Iceland, Norway, Sweden and the UK—is examined. The potential economic rents and the capacity reduction necessary to achieve these rents in each of the fisheries are also estimated. Reasons why IVQs have not achieved their potential economic benefits in these fisheries are also examined. 相似文献
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Cecilia Eriksson Harry Burton Stuart Fitch Martin Schulz John van den Hoff 《Marine pollution bulletin》2013,66(1-2):199-208
The worlds’ oceans contain a large but unknown amount of plastic debris. We made daily collections of marine debris stranded at two sub-Antarctic islands to establish (a) physical causes of strandings, and (b) a sampling protocol to better estimate the oceans’ plastic loading. Accumulation rates at some beaches were dependent on tide and onshore winds. Most of the 6389 items collected were plastic (Macquarie 95%, Heard 94%) and discarded or lost fishing gear comprised 22% of those plastic items. Stalked barnacles (Lepas spp.) were a regular attachment on Macquarie debris but not at Heard Island. The daily accumulation rate of plastic debris on Macquarie Island was an order of magnitude higher than that estimated from monthly surveys during the same 4 months in the previous 5 years. This finding suggests that estimates of the oceans’ plastic loading are an order of magnitude too low. 相似文献
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The East Central climate division of Louisiana is used as a case study to evaluate relationships between divisional climate data and the 15 largest flood events on each of seven rivers during a 25-year period. Monthly precipitation and moisture surplus (a water-budget component) are correlated with number of rivers in flood within the division; the Palmer Drought Severity Index (PDSI) is not. Although divisional data sets index climatic variability for nearly 100 years, this study indicates that some cautions should be considered when applying divisional data to flood analyses. [Key words: water budget, PDSI, climate division data, flooding, storm precipitation.] 相似文献
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ABSTRACTConcerns about the water–energy–food (WEF) nexus have motivated many discussions regarding new approaches for managing water, energy and food resources. Despite the progress in recent years, there remain many challenges in scientific research on the WEF nexus, while implementation as a management tool is just beginning. The scientific challenges are primarily related to data, information and knowledge gaps in our understanding of the WEF inter-linkages. Our ability to untangle the WEF nexus is also limited by the lack of systematic tools that could address all the trade-offs involved in the nexus. Future research needs to strengthen the pool of information. It is also important to develop integrated software platforms and tools for systematic analysis of the WEF nexus. The experience made in integrated water resources management in the hydrological community, especially in the framework of Panta Rhei, is particularly well suited to take a lead in these advances. 相似文献